Help! Floats keep filling with fuel
Posted: Sat Jun 28, 2025 5:42 am
Hi all,
Having an annoying issue, I cleaned and rebuilt the carbs on my UK ‘98 600 and the bike was running nice, then about 3 weeks later I went to start it up and noticed that it was dumping fuel out of the carb overflow.
So I stripped it down and found that the float in cylinder 4 was full of fuel and therefore wasn’t doing its primary job of floating.
Putting it down to a one off didn’t float I ordered another rebuild kit, replaced the float and all was good.
About a month later, went on a road trip, about 3 hours away from home noticed when I pulled up at some traffic lights that it was dumping fuel again. Stopped the carbs down in a service station and sure enough, carb number 4’s float had filled with fuel and stopped floating again. So I bent the tang up so that no fuel could enter the bowl, and rode it home on 3 cylinders.
Once again, bought a new rebuild kit, tried to avoid the cheap ones from china on eBay and for good measure replaced all of the floats and needles in all of the bowls. Got her back up and running again.
Jump to this weekend, rode 220 miles to the ABR festival, without a hitch, went to start her up today and she is dumping fuel again!
Stripped it down and now carb number 3’s float has filled with fuel!
Is this a common problem? Am i doing something wrong? Surely not all carb kits can be this bad quality?!
Is it okay for me to shut it off and run on 3 again? Could I link up the bleed screws with a hose between 3 and 4 and have the float bowl fill that way and shut the needle with the tang again?
I also have a persistent drip of oil coming out of the hole in the air box that sits inside the air filter, not sure if this is related, or causing it, any ideas??
All help and ideas appreciated!
Having an annoying issue, I cleaned and rebuilt the carbs on my UK ‘98 600 and the bike was running nice, then about 3 weeks later I went to start it up and noticed that it was dumping fuel out of the carb overflow.
So I stripped it down and found that the float in cylinder 4 was full of fuel and therefore wasn’t doing its primary job of floating.
Putting it down to a one off didn’t float I ordered another rebuild kit, replaced the float and all was good.
About a month later, went on a road trip, about 3 hours away from home noticed when I pulled up at some traffic lights that it was dumping fuel again. Stopped the carbs down in a service station and sure enough, carb number 4’s float had filled with fuel and stopped floating again. So I bent the tang up so that no fuel could enter the bowl, and rode it home on 3 cylinders.
Once again, bought a new rebuild kit, tried to avoid the cheap ones from china on eBay and for good measure replaced all of the floats and needles in all of the bowls. Got her back up and running again.
Jump to this weekend, rode 220 miles to the ABR festival, without a hitch, went to start her up today and she is dumping fuel again!
Stripped it down and now carb number 3’s float has filled with fuel!
Is this a common problem? Am i doing something wrong? Surely not all carb kits can be this bad quality?!
Is it okay for me to shut it off and run on 3 again? Could I link up the bleed screws with a hose between 3 and 4 and have the float bowl fill that way and shut the needle with the tang again?
I also have a persistent drip of oil coming out of the hole in the air box that sits inside the air filter, not sure if this is related, or causing it, any ideas??
All help and ideas appreciated!